On the basis of Shay's ulcer model, we have studied the effects of food re. striction time on the experimental gastric ulcer in rats. The results indicat that each restricted group forms gastric ulcer after ligation of pylorus 18 hr. There are a postive correlation between the restricted time and the severity of gastric ulcer, and a negative correlation between the severity of gastric ulcer and the amount of gastric acid secretion. We suggested that Shay's ulcer model does not belong to peptic ulcer, but belonges to one of the stress ulcers. The restricted time may play an important role in the mechanism for this ulcer model.

Effects of emodin and rhubarb polysaccharides on the cytoplasmic free calcium in Iymphocyte of mice were studied with the latest generation fluorescent indicator Fura-2. Resultsshowed that emodin at a final concentration of 18.5 ?mol/L promotes the influx of extracellular ca2+ of lympbocytes. Polysaccharides inhibit the influx of Ca2+ aud the release of Ca2+from intracellular stores and their effects are dose dependent. Therefore, it suggests thatemodin can improve the immune function of spleen lymphocytes, but the polysaccharides caninhibit their function. This may be ouc of the theoretical evidences of the biphasic regulationeffects of rhubarb.

Objective To evaluate the relationships of the expression of orexin A in hypothalamus with hyperleptinemia, hyperinsulinism, and hyperlipidemia in alimentary obesity rats.Methods The alimentary obesity rat model was induced by high-fat diet in Wistar rats. The levels of leptin, insulin, C-peptide, total cholesterol (TC) and triglyeride (TG) were detected by luminescent immunoassay and biochemistry enzymic method. The gene expression of orexin A in rat hypothalamus was detected by real-time PCR. The correlation between orexin A and leptin was analyzed. Results After 8 weeks of high-fat diet feeding, the body weight, Lee's index, blood glucose, TG and TC significantly increased in obesity rat group (P＜0. 01). The levels of serum leptin, insulin and C-peptide were significantly higher in obesity rats than in controls [( 1.74±0. 36)μg/Lvs. (1.27±0.11) μg/L, (35±5) MIU/L vs. (23±4) MIU/L, (0.21±0.04) μg/L vs.(0. 14±0. 03) μg/L respectively, P＜0.01]. However, the level of orexin A mRNA was lower in obesity rats than in controls (6.8±2.3 vs. 14.5±3.6, t=-8.06, P＜0.01). The correlation coefficient (r) of orexin A mRNA with serum leptin, insulin, and C-peptide in alimentary obesity rat were -0. 726 (P＜0.01), -0. 506 (P＜0.01) and -0. 664 (P＜0.01), respectively. Conclusions High-fat diet can induce leptin-resistance and alimentary obesity in Wistar rat. The down-regulation of orexin A in rat hypothalamus would be correlated closely to the leptin and insulin resistance in alimentary obesity.

[Summary] The neuropeptides orexin A and orexin B are involved in numerous central regulation processes such as energy homeostasis,sleeping behaviour,and neuroendocrine activities.Orexin receptors are expressed in a variety of tissues besides the brain,adrenal gland for example.The article reviews the effect of orexin on adrenal gland function.